1. Prioritizing Booster Pump Station Improvements Tom Peters, P.E. May 2, 2008

2. City of Bellevue WBPS Evaluation Overview ▼ Owns and operates 23 major water booster pump stations ▼ Pumped water service for over 60% of customers ▼ First overall technical evaluation of all pumping facilities and equipment

3. City of Bellevue WBPS Evaluation Project Goals ▼ Efficient distribution of maintenance dollars  Identify facilities whose failure significantly impacts system reliability  Rank WBPS in order of needed improvement  Develop costs to upgrade and Improve WBPS reliability  Asset management “building block ”

5. City of Bellevue WBPS Evaluation History ▼ Grown from merger and assumption of old water districts ▼ Some facilities developer constructed ▼ Historically wholesale water purchase from City of Seattle ▼ Member of Cascade Water Alliance

6. City of Bellevue WBPS Evaluation Project Challenges ▼ Multiple pump types ▼ Varying levels of building quality ▼ Below grade vaults ▼ Inefficient location of emergency power ▼ Absence of re- chlorination facilities

7. City of Bellevue WBPS Evaluation Project Challenges

8. Pump Station Information and Data ▼ Thorough review of as-builts, maintenance records, water production and previous studies ▼ Analysis of peak and average day consumption, by pump station and operating zone. ▼ Rigorous assessment of each pump station condition, with video taped operator interview ▼ Development of 10 system schematics summarizing basic system information

10. Ranking Pump Stations Ranking WBPS Needs PairedComparison Normal Operation PairedComparison Emergency Operation

11. Ranking Evaluation Criteria

12. Pump Station Score Card

13. Normal Operating Ranking

14. Ranking Pump Stations Ranking WBPS Needs PairedComparison Normal Operation PairedComparison Emergency Operation

15. City of Bellevue WBPS Evaluation Risk Based Assessment ▼ Risk = Hazard Probability X Vulnerability X Consequence ▼ Hazards impacting multiple facilities pose the greatest risk l Regional power outage l Earthquake l Flooding ▼ Redundancy, properly placed, provides effective mitigation

16. Sample Risk Ranking

17. Emergency Operating Scenario

18. Combined Rankings

19. SUMMARY ▼ WBPS assessed: 23 ▼ WBPS requiring improvements: 21 ▼ Total cost all improvements: 21.4 M ▼ Average cost of replacement (5): 2.9 M ▼ Average cost of improvements (16): 0.43 M